Apple trees CAN grow in Wyoming but you need to know some core facts

n apple a day keeps the doc- and also provide fruit to eat and make insect pests) in your apple trees. Ator away … at least it can’t hurt, cider with. Win, win! You will have to develop a pest right? But, can apples grow in management plan. And, I have always loved eating apples. Wyoming? 4. You need to prune trees every As a kid, my mom would have to There are a few things to know year. stop me before I ate all the apples in upfront. the fruit bowl, and still today you can 1. It will take three to five years after Apple Varieties Apples are among the cold-har- catch me eating an apple just about planting before you start picking diest fruit trees. Of the thousands of every day. apples. apple varieties out there, many will Naturally, as a gardener, when 2. There will be years no apples survive Wyoming’s cold winters. You I choose plants to grow, I choose will grow. Freezing temperatures can’t choose just one. Apples require plants I will enjoy either for their ap- when the trees are blooming can cross-pollination, so you will need to pearance, for their function in the result in a partial or complete loss plant at least two varieties for pollina- landscape or garden, or because I will of fruit that year. tion to occur and for fruits to develop. enjoy eating them! Apple trees can 3. You will eventually find fire blight Crabapples are also good pollinizers be attractive plants in the landscape (and probably other disease and for apples.

4 BARNYARDS & BACKYARDS Some varieties known to thrive in Of the thousands Pruning Wyoming include Snowsweet, Zestar, Start training apple trees at plant- Honeycrisp, Cortland, Haralred, Lodi, of apple varieties ing time, and prune annually through- McIntosh, and State Fair. out there, many will out the life of the tree. Pruning is one Rootstock of the most important maintenance survive Wyoming’s practices required to get good yields, A rootstock is a root system manage diseases, and to control from one variety with another variety cold winters. You the size of the trees. Without proper grafted on top. Rootstocks are either can’t choose just one. pruning, apples tend to overproduce, dwarf, semi-dwarf, or standard, meaning they produce a lot of apples, meaning the rootstock is controlling Apples require cross- but they are small and lack flavor. the overall size of the tree. Selecting pollination, so you Properly pruned trees will have fewer, rootstock for your apple trees may be but larger, apples with higher sugar a little confusing and overwhelming. will need to plant at content and better flavor. I’ve found that, while there are many least two varieties for Apples should be trained to a options out there, as a consumer you central leader with properly spaced have limited options beyond “what is pollination to occur and lateral branches off the main trunk available” from the nursery. for fruits to develop. (central leader). See bit.ly/wyoap- Dwarf rootstock will produce plepruning. If a young tree does trees that grow to 8-10 feet tall, which not have any lateral branches, top is ideal if space is limited. Dwarf trees pruning and harvesting can be done the tree at 3-4 feet tall to encour- require staking or trellising for sup- from the ground and does not require age branches to emerge below port, otherwise they may topple over a ladder to reach most of the apples. the pruning cut. Once branches from the weight of the fruit. Dwarf Standard trees will eventually start have emerged, select 3-5 branches rootstocks tend to do better in mild producing most of its apples toward that are 3-4 feet above the ground. climates and may not be good choices the tops of the trees where they are These will become the lowest per- for many areas in Wyoming. harder to get. manent branches on the tree. Wide Semi-dwarf rootstock will pro- Again, you may not be able to branch angles are desirable. Leave duce trees 15 feet tall and wide. choose the exact rootstock from the one upright branch to become the Semi-dwarf trees are often good nursery, but it is worth asking if any central leader. Remove everything choices for backyards and commer- fire blight-resistant root stock is avail- else below these lower branches, cial production. able. Rootstock not only determines including root suckers. These low- Apple trees on standard root- the size of the tree, but also the tree’s est branches are called scaffold stock may grow 25-50 feet tall. The susceptibility to diseases like apple branches and should be spaced nice thing about smaller trees is that scab and fire blight. evenly around the trunk.

FALL 2017 5 As the tree grows, select three to Fire blight infects many apple variet- Coddling moth is a common five more branches 2-3 feet above the ies, infecting flowers, twigs, and fruit. insect pest in apple orchards, espe- scaffold branches. These will develop Symptoms often appear when new cially in dry areas. Coddling moths the next scaffold whorl of branches. leaves turn brown, twigs discolor emerge around bloom time and lay A mature semi-dwarf apple tree will and droop with a classic shepherd’s eggs on leaves and fruit. When eggs have three scaffold whorls with the crook, and cankers appear on branch- hatch, the larvae begin feeding on lowest branches being the longest es and sometimes the trunk. Pruning the fruit by tunneling into the apples. and the upper branches the shortest, to remove infected branches is the Small holes with frass around the giving the tree a pyramidal shape. best control method. Pruning will not hole is an indication of coddling moth eliminate fire blight but can keep the presence in the apple. Insecticides Flowering and Fruit disease in check and reduce spread- are available for homeowners and Production ing the disease. commercial growers if coddling moth Apples flower and produce fruit Apple scab is a fungal disease infestations are severe. on spurs (short, lateral branches usu- often noticed in spring and summer ally 1-2 inches long). These spurs as dark, roughly circular spots on Wyoming Apple Hardiness grow on 2-year-old wood. Keep this in the leaves. The fungus also infects Study mind when pruning. You do not want fruit. Fruit will have small, raised Thanks to a specialty crop grant to remove too much wood. Make brown spots similar in appearance through the Wyoming Department sure to leave plenty of spurs on the to a scab. The disease affects the of Agriculture, I’m conducting an tree. Also, be careful when harvest- quality of the fruit, and infected apple variety study, examining winter ing apples not to accidentally pull the leaves often drop prematurely, which hardiness in 15 varieties and different spurs off with the apples. stunts growth and weakens the tree. rootstocks. The trees were planted Sanitation is the key to reducing last spring. Apple Diseases and Pests Results from this study will help Fire blight is the most common apple scab. Rake and destroy leaves develop a list of apple varieties rec- disease problem with apple trees. in fall to prevent the disease from spreading from year to year. ommended for Wyoming. The apple varieties in this study include September Wonder Fuji, Ben Davis, Yellow Transparent, Orleans Antique, Enterprise, Arkansas Black, Cortland, Liberty, Freedom, McIntosh, Zestar, Honeycrisp, SnappyMac, Lodi, and Haralred. We look forward to seeing which varieties are suitable for Wyoming and sharing that information with you.

Just how many times Chris Hilgert has seen a doctor is none of our business, but darn, we sure are curious if the apple strategy works. He is the Master Gardener state coordinator and a member of the Department of Plant Sciences at the University of Wyoming. He can be reached at (307) 766-6870 or at [email protected].

6 BARNYARDS & BACKYARDS